Fork lift truck



Oct. 30, 1945. v CLAPP 2,387,744

FORK LIFT TRUCK Filed April 30, 1945 IN V EN TOR.

crane.

Patented Oct. 30, 1945 UNITED TATES- PATENT 8 OFFICE Pasco,-Wash.

Application April 30, 1945, Serial No. 591,044

2 Claims. (Cl. 214-65)- Granted under the act of March 3, 1883, as

' amended April 30, 1928; 370 0. G. '757) The invention describedherein, if patented may be manufactured and used by or for theGovernment for governmental purposes, without the payment to me of anyroyalty thereon.

This invention relates to industrial trucks of the fork-lift type andrefers specifically to an attachment thereto whereby a conventionalfork-' lift truck may be temporarily converted into a An object of thisinvention is to provide a I means which will enable quick and easyconversion and reconversion from fork-lift truck to crane and viceversa.

Another object is to provide a means for temporarily converting afork-lift truck which does not require the use of bolts or similarfastening devices. v 7

Further objects, advantages andfeatures will be apparent from thefollowing specification read in conjimction with the accompanyingdrawing in which:

Figure 1 is a side elevational view of the front of a fork-lift truckequipped with the crane assembly 01' my invention;

Figure 2 is a top plan view of the crane assembly of my inventionshowing the manner in which it fits on the truck lifting fingers, and

Figure 3 is a sectional view taken along the lines 8-4 of Figure .2.

Industrial trucks of the fork-lift type are used in 'warehouses,factories and docks to move matriel from one point to another. Themateriel is carried on pallets which are picked up by lift- In themovement of materiel from one location .to another, especially inwarehouses, efficient use of storage space requires that as manyarticles as possible be piled tier upon tier. Articles of more compactdimensions present little difficulty. Howevenin the case of elongatedarticles, it is tachment whereby the conventional fork-lift truck may betemporarily converted to a crane, thus dispensing with the requirementfor additional warehouse equipment. The crane is used to move materielwhich cannot beadequately handled by the fork-lift truck operating inthe normal manner.

Referring to the accompanying drawing, and more specifically to Figure 1thereof, the front of a conventional fork-lift truck has been shown tomore clearly illustrate the relationship which the attachment of myinvention bears thereto. The truck, indicated generally by the numerali, is provided at its forward end with drive wheels 2. Lifting mechanismsupports 3 are attached to the front of the truck by brackets 4.Substantially. L-shaped lifting fingers 5 are. pivotally mounted on ashaft 6 which is mounted in a frame 1. The frame 1 comprises a pair ofvertica1 plates 24 and a bracket 25 in which the shaft 6 is supported.This frame I is attached to the lifting mechanism of the fork-lift truckwhich is mounted between the supports 3. In the conventional thehorizontal.

' ingfingers mounted at. the front of the truck. a

difficult and sometimes impossible to stack them veryhigh. by using theconventional fork-lift truclrin the conventional manner.

Thusit may be seen that the normal use of the conventionalfork-lifttruck is limited in its scope. Other'equipment must be available toproperly handle articles which do not readily lend themselves tohandlingby fork-lift trucks. An object' of my invention, therefore, is toprovide an atfork-lift truck, vertical arms 26 of the lifting fingers 5normally rest against the vertical plates 24.

Generally speaking, the attachment which enables the truck to operate asa crane comprises two basic assemblies, a heel support 8 and a boomextension 8. The heel support 8 cants the lifting fingers 5 at a fixedangle of inclination from The boom extension 9 is mounted on the freeend of the lifting fingers 5 and forms an extension thereof.

The heel support 8 is metal casting comprising side frames l0 and IIwith lugs I 2 and I3 projecting from the upper rear ends thereof, a rearplate I! and a front plate I5 disposed at the rear and frontrespectively between said side frames.

The boom extension 9 is a metal casting comprising a frame I 6, an uppercenter cross member I! and a lower center cross member l8 disposedbetween the sides of the frame H5 at the center thereof, an upper rearcross member I 8 and a lower rear cross member 20 disposed be-. tweenthe sides of the frame l8 at the base thereof, and stops 2| disposedbetween the upper and the lower center cross members I! and I8 andadjacent each inner wall of the frame iii. An eye bolt 22 is mounted atthe apex of the frame 16. To it may be connected any suitable mechanism23 for engaging the wor In preparing the fork-lift truck for 'use as acrane, the heel support 8 is installed first. It is threaded upon thelifting fingers 5 with its rear 2 Y ase'mee I firmly supports thelifting fingers t in position at a fixed angle of inclination from thehorizontal.

The boom extension 9 is mounted on the free end of the lifting fingers 5by threading the frame l8 upon the fingers, with the .cross member l9above and the cross member 20 beneath the fingers, until the tips of thefingers contact the stops 2| projecting inwardly from the frame It at apoint adjacent the center cross members i1 and I8, as shown in Figure 3.Due to the angle of inclination of the lifting fingers, no bol ts orsimilar means are necessary to maintain .the boom extension in position.The apex of the frame It of the boom extension 9 is provided with aconventional means, such as an eye bolt 22, for supporting a tongassembly 23 or some similar means for engaging the object or article tobe moved.

Only a very few minutes are required to convert the truck for use as acrane. No bolts or similar locking or securing devices are necessarywhen installing the boom extension and the heel support. The heelsupport is constructed so that any downward or rearward force exerted onthe lifting fingers or on the heel support is transmitted to thevertical plates 24, thus locking the heel support more securely'inplace. Movement of the boom extension 9 along the longitudinal axis ofthe lifting fingers 5 is limited by the stops 2| and by the angle ofinclination of the liftin fingers themselves. Movement of the boomextension along the vertical axis of the lifting fingersis limited bythe center cross members I! and I8, and the rear cross members l8 and20.

/ and a frame to which the end of one arm of said load carrying meniberis connected: of a support," 5 upon which said lead carrying memberrests, for canting said laterally extending load carrying when inposition. the heel support 8 supports the lifting fingers I at a fixedangle of inclination from the horizontal. In order that the greatestpossible operating range of the fork lift truck lifting mechanism in thevertical plane be utilized. it is preferred that this canting besuflicient to permit the work-engaging mechanism 23 to clear the flooror ground when the lifting fingers have been moved to their'lowestposition in the vertical plane.

I claim:

1. The combinatiomwith a lift truck having a vertically movable,substantially L-shaped, load carrying member extending laterallytherefrom,

member at a predetermined angle with respect to said frame, said supportcomprising an apertured frame threaded upon said load carrying memberand having a portion thereof disposed between said member and saidframe; and means mounted on the free end of said load carrying member tosupport a load grasping means.

2. The combination, with a lift truck having a vertically movable,substantially L-shaped, load carrying member extending laterallytherefrom, and a frame to which the end of orie arm of said loadcarrying member is connected of a support, upon which saidload carryingmember rests, for canting said laterally extending load-carrying memberat a predetermined angle with respect to said frame, said supportcomprising an apertured frame threaded upon said load carrying memberand having a portion thereof disposed between said member and said frameadjacent the juncture of the arms I of the substantially L-shaped loadcarrying member; and means mounted on the free end of said load carryingmember to support a load grasping means.

GEORGE L. CLAPP.

